AMNA NAWAZ: Finally, tonight, we have an excerpt from Judy Woodruff's podcast "In Pursuit of Happiness."

This week, Judy explores how America's national parks preserve not only the nation's most spectacular landscapes, but also some of its most important history.

Her guest is Jason Epperson, a podcaster and R.V.

traveler who spent years getting to know the parks with his family.

JUDY WOODRUFF: Do you have favorites that you like to share... JASON EPPERSON, Host, "PARKography": I do.

JUDY WOODRUFF: ... that you have been to over and over again?

JASON EPPERSON: Yes, Fort Sumter is really interesting because it's one of these cool coastal forts.

We have all these coastal forts all along the East Coast, where they were sort of built right after first the Revolutionary War and the War of 1812 to protect from, of course, battleships.

And during the Civil War, it was very clear that they were absolutely useless.

But Fort Sumter is where the first shots of the Civil War were fired.

And when you go there and you visit and you experience it.

You take a tour out there, you get on a boat, and ranger takes you through the place, and they invariably show you the bricks that the fort is built out of.

And these bricks were forged by enslaved people.

And when you go look closely at them, you see in the bricks fingerprints, and not just fingerprints of enslaved people, but enslaved children.

And you can look at sculptures of people all day.

It's -- a sculpture is a representation of somebody's idea of what somebody looked like.

When you see somebody's fingerprint in something, it's sort of this indelible idea that they were there.

JUDY WOODRUFF: Yes.

JASON EPPERSON: And it really brings home sort of this idea of what the Civil War was fought for at the place where it began.

I love that history.

I love White Sands National Monument.

White Sands in New Mexico is our children's favorite place in the National Park Service.

They feel like they're in an episode of Star Wars.

JUDY WOODRUFF: Really?

JASON EPPERSON: It's one of the few parks -- most of the parks, you have got to stay on a trail, right?

At White Sands, you can just kind of go anywhere you want to.

And it is these weird white gypsum dunes.

It's not actual sand.

It's gypsum, which is what drywall is made out of, in the middle of New Mexico that sort of contrasts completely with the landscape.

And at White Sands, they have found the oldest human footprints in existence.

White Sands -- just in the last couple years, they have found footprints in White Sands that make humans older than we thought they were in the United States.

JUDY WOODRUFF: Ah.

JASON EPPERSON: And so the human history goes way, way back, right?

It's beyond the Native Americans, and it goes very far back in the National Park Service.

But then this White Sands missile site, which is right next door, is also where the atomic bomb was tested.

And in White Sands National Park and in areas around it, you can still find slivers of green glass, which is which is... JUDY WOODRUFF: Oh, gosh.

JASON EPPERSON: Was instantly formed when the when the atomic bomb was first tested, so, again, beautiful natural area that is sort of this surprise out of the middle of nowhere, but has this wild human history to it.

AMNA NAWAZ: And you can watch that full episode of "In Pursuit of Happiness" on our YouTube page or wherever you get your podcasts.